Compound essential oil for hair care and massage

Abstract

The invention discloses compound essential oil for hair care and massage, which consists of multiple layers of pressure response type release microspheres and essential oil compositions filled in the multiple layers of pressure response type release microspheres and among gaps of each layer, the material of the multilayer pressure response type release microspheres comprises 80-99 wt% of sodium alginate and 1-20 wt% of low molecular weight poly (N-isopropylacrylamide), and the essential oil composition comprises rosemary essential oil, sandalwood essential oil, ginger essential oil, lavender essential oil, cypress essential oil and base oil. The essential oil is coated by preparing the multi-layer pressure response type release microspheres, in the hair massage process, all the coating layers become fragile layer by layer from outside to inside, then the coating layers are broken under the massage pressure, essential oil components are released layer by layer, discomfort or anaphylaxis caused by too large dosage of the essential oil components in the initial stage can be avoided, and the hair massage effect is improved. Meanwhile, volatilization waste of essential oil components can be avoided, and the maintenance and massage effects are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of hair care, and particularly relates to a compound essential oil for hair care massage. Background Art

[0002] Massage is a common way of hair care. Scientific massage techniques can improve the metabolism of hair follicles, promote hair growth, and improve hair quality. Adding some plant essential oils during the massage can further nourish the hair, enable the absorption of the nutritional components in the essential oils, thereby improving the scalp environment and making the hair healthier. In addition, some essential oils also have the function of repairing damaged hair strands, which helps to restore the vitality of the hair.

[0003] Currently, the essential oils for hair care massage used in the market are all compound essential oils directly obtained by mixing several plant essential oils in proportion. Before massage, they are evenly coated on the scalp and then massaged. This has the following problems: (1) Directly coating the compound essential oil on the human scalp at one time will cause the scalp to directly contact a large amount of essential oil components. Coupled with the influence of massage friction, the high-concentration essential oil may directly stimulate the scalp. Especially for sensitive skin types, it may cause discomfort or allergic reactions; (2) Coating a large amount of essential oil at one time will make it difficult for the essential oil components to be absorbed in a short time. And as the massage progresses, a large amount of essential oil components volatilize, resulting in waste and further affecting the maintenance effect.

[0004] Therefore, we need to optimize the existing essential oils for hair care massage in the market to overcome the above problems. Summary of the Invention

[0005] The purpose of the present invention is to provide a compound essential oil for hair care massage, which solves the problems that the high-concentration essential oil in the existing compound essential oil for hair care massage is easy to stimulate the scalp and cause discomfort or allergic reactions, and is easy to cause volatilization and waste of essential oil components, thereby affecting the maintenance effect.

[0006] The present invention realizes the above purpose through the following technical solutions:

[0007] A compound essential oil for hair care massage, the compound essential oil is composed of multi-layer pressure-responsive release microspheres and an essential oil composition filled inside the multi-layer pressure-responsive release microspheres and between the gaps of each layer. Among them, the material of the multi-layer pressure-responsive release microspheres includes 80-99wt% of sodium alginate and 1-20wt% of low molecular weight poly(N-isopropylacrylamide).

[0008] Further improvement lies in that the molecular weight of the low molecular weight poly(N-isopropylacrylamide) is 2000-10000.

[0009] A further improvement lies in that the number of layers of the multi-layer pressure-responsive release microspheres is 3 - 5 layers.

[0010] A further improvement lies in that the preparation method of the compound essential oil is as follows:

[0011] S1. Mix an aqueous sodium alginate solution with a concentration of 1.5 - 2.5 wt% and an aqueous solution of low molecular weight poly(N-isopropylacrylamide) with a concentration of 1 - 3 wt% in proportion to obtain a coating solution;

[0012] S2. Mix the essential oil composition and the coating solution at a mass ratio of 1:3 - 5, homogenize at high speed to form a primary emulsion, then drop the primary emulsion into a CaCl₂ solution with a mass concentration of 2 - 2.5%, stir magnetically at a speed of 180 - 250 rpm, carry out a cross-linking reaction for 10 - 15 min to form solid microspheres with a diameter of 50 - 100 μm, and wash with deionized water after centrifugal separation;

[0013] S3. Immerse the solid microspheres in the essential oil composition, carry out ultrasonic treatment to enable the essential oil composition to adsorb on the surface and pores of the solid microspheres, and then centrifuge to remove the excess essential oil;

[0014] S4. Suspend the solid microspheres in the coating solution, and carry out low-temperature atomization drying using a pressure atomizer. The atomized droplets are directly sprayed into a cold trap at -18°C to -20°C, and a CaCl₂ solution with a mass concentration of 1 - 1.5% is sprayed in the cold trap for primary cross-linking. Then, immerse the sprayed solid microspheres in a CaCl₂ solution with a mass concentration of 1 - 1.5% for 4 - 6 min for secondary cross-linking;

[0015] S5. Take out the solid microspheres and place them in a freezing tray, freeze them to -70°C to -90°C, and then transfer them to a freeze dryer, and dry them at -45°C to -55°C for 24 - 48 h to obtain re-coated solid microspheres;

[0016] S6. Repeat steps S3 - S5 multiple times until the target coating layer number is reached.

[0017] A further improvement lies in that in step S2, the conditions for high-speed homogenization are: homogenize at a rotation speed of 10000 - 15000 rpm at 20 - 25°C for 3 - 6 min.

[0018] A further improvement lies in that in step S2, the flow rate of dropping the primary emulsion is 0.4 - 0.6 mL / min.

[0019] A further improvement lies in that in step S3, the conditions for ultrasonic treatment are: carry out ultrasonic treatment at 20 - 25°C with a power of 100 - 150 W for 8 - 12 min.

[0020] Further improvement lies in that in step S4, the conditions for low-temperature atomization drying are: the pressure is 0.7 - 0.9 MPa, and the temperature is 4 - 10 °C.

[0021] Further improvement lies in that by weight percentage, the essential oil composition includes: 1 - 3% rosemary essential oil, 1 - 2% sandalwood essential oil, 0.5 - 1% ginger essential oil, 1 - 3% lavender essential oil, 1 - 2% cypress essential oil, and the balance is coconut oil as the base oil.

[0022] The beneficial effects of the present invention are as follows: The present invention encapsulates essential oils by preparing multi-layer pressure-responsive release microspheres. Among them, sodium alginate provides appropriate mechanical strength for the encapsulation layer, while low-molecular-weight poly(N-isopropylacrylamide) is a temperature-sensitive material. After reaching the phase transition temperature (about 32 °C), due to its own hydrophobicity and chain segment contraction, the encapsulation layer becomes fragile. Therefore, during the hair massage process, each encapsulation layer from the outside to the inside gradually becomes fragile (the scalp heat is transferred layer by layer from the outside to the inside), and then ruptures under the massage pressure, enabling the gradual release of the essential oil components. This can avoid discomfort or allergic reactions caused by excessive initial usage of essential oil components, and at the same time can avoid the volatilization waste of essential oil components, improving the maintenance massage effect. Specific Embodiments

[0023] The following further describes the present application in detail with reference to embodiments. It is necessary to point out here that the following specific embodiments are only used to further illustrate the present application and cannot be construed as limiting the protection scope of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application based on the above application content.

[0024] I. Main raw materials:

[0025] Sodium alginate: Purchased from Guangdong Hongyou Biotechnology Co., Ltd.

[0026] Poly(N-isopropylacrylamide): Its molecular weight is 2000 - 10000, purchased from Shenzhen Regent Biochemical Technology Co., Ltd.

[0027] The main essential oil components are shown in Table 1 below:

[0028] Table 1: Essential oil raw materials and introduction

[0029]

[0030] II. Specific implementation experiments

[0031] Example 1

[0032] A compound essential oil for hair care massage, the compound essential oil is composed of three layers of pressure-responsive release microspheres and an essential oil composition filled inside the three layers of pressure-responsive release microspheres and between the gaps of each layer. Among them, the material of the three layers of pressure-responsive release microspheres includes 99 wt% of sodium alginate and 1 wt% of low molecular weight poly(N-isopropylacrylamide) with a molecular weight of 2000; by weight percentage, the essential oil composition includes: 3% rosemary essential oil, 1% sandalwood essential oil, 1% ginger essential oil, 3% lavender essential oil, 2% cypress essential oil, 90% coconut oil.

[0033] The preparation method of the compound essential oil is as follows:

[0034] S1. Mix the aqueous solution of sodium alginate with a concentration of 1.5 wt% and the aqueous solution of low molecular weight poly(N-isopropylacrylamide) with a concentration of 1 wt% evenly according to the ratio to obtain a coating solution;

[0035] S2. Mix the essential oil composition and the coating solution at a mass ratio of 1:3, and homogenize at high speed (homogenize at a speed of 10000 rpm for 6 min at 20 - °C) to form a primary emulsion. Then, drop the primary emulsion into a CaCl2 solution with a mass concentration of 2% at a speed of 0.4 mL / min, and stir magnetically at a speed of 180 rpm for 10 min for cross-linking reaction to form solid microspheres with a diameter of 50 ± 5 μm. After centrifugal separation, wash with deionized water;

[0036] S3. Immerse the solid microspheres in a sufficient amount of essential oil composition and perform ultrasonic treatment (ultrasonic treatment at a power of 100 W for 12 min at 20 °C) to make the essential oil composition adsorb on the surface and pores of the solid microspheres, and then centrifuge to remove the excess essential oil;

[0037] S4. Suspend the solid microspheres in a sufficient amount of coating solution and perform low-temperature atomization drying using a pressurized atomizer (pressure is 0.7 MPa, temperature is 10 °C). The atomized liquid droplets are directly sprayed into a -18 °C cold trap, and a CaCl2 solution with a mass concentration of 1% is sprayed in the cold trap for primary cross-linking. Then, immerse the solid microspheres after spraying in a CaCl2 solution with a mass concentration of 1% for 4 min for secondary cross-linking;

[0038] S5. Take out the solid microspheres and place them in a freezing tray, freeze them to -70 °C, and then transfer them to a freeze dryer and dry at -45 °C for 24 h to obtain the re-coated solid microspheres;

[0039] S6. Repeat steps S3 - S5 multiple times until the target coating layer number is reached.

[0040] Example 2

[0041] A compound essential oil for hair care massage, which is composed of four layers of pressure-responsive release microspheres and an essential oil composition filled inside the four layers of pressure-responsive release microspheres and between the gaps of each layer. Among them, the material of the four layers of pressure-responsive release microspheres includes 90 wt% sodium alginate and 10 wt% low molecular weight poly(N-isopropylacrylamide) with a molecular weight of 5000; by weight percentage, the essential oil composition includes: 2% rosemary essential oil, 1.5% sandalwood essential oil, 1% ginger essential oil, 2% lavender essential oil, 1.5% cypress essential oil, and 92% coconut oil.

[0042] The preparation method of this compound essential oil is as follows:

[0043] S1. Mix uniformly an aqueous solution of sodium alginate with a concentration of 2 wt% and an aqueous solution of low molecular weight poly(N-isopropylacrylamide) with a concentration of 2 wt% in proportion to obtain a coating solution;

[0044] S2. Mix the essential oil composition and the coating solution at a mass ratio of 1:4, and homogenize at high speed (homogenize at a speed of 12000 rpm for 4 min at 22 °C) to form a primary emulsion. Then, drop the primary emulsion into a CaCl2 solution with a mass concentration of 2.5% at a speed of 0.5 mL / min, and stir magnetically at a speed of 200 rpm for 12 min for cross-linking reaction to form solid microspheres with a diameter of 80 ± 5 μm. After centrifugal separation, wash with deionized water;

[0045] S3. Immerse the solid microspheres in a sufficient amount of essential oil composition and perform ultrasonic treatment (ultrasonic treatment with a power of 120 W for 10 min at 22 °C) to enable the essential oil composition to adsorb on the surface and pores of the solid microspheres, and then centrifuge to remove the excess essential oil;

[0046] S4. Suspend the solid microspheres in a sufficient amount of coating solution and perform low-temperature atomization drying using a pressurized atomizer (pressure is 0.8 MPa, temperature is 8 °C). The atomized liquid droplets are directly sprayed into a -20 °C cold trap, and a CaCl2 solution with a mass concentration of 1.5% is sprayed in the cold trap for primary cross-linking. Then, immerse the solid microspheres after spraying in a CaCl2 solution with a mass concentration of 1.5% for 5 min for secondary cross-linking;

[0047] S5. Take out the solid microspheres and place them in a freezing tray, freeze them to -80 °C, and then transfer them to a freeze dryer and dry at -50 °C for 36 h to obtain re-coated solid microspheres;

[0048] S6. Repeat steps S3 - S5 multiple times until the target coating layer number is reached.

[0049] Example 3

[0050] A compound essential oil for hair care massage, the compound essential oil is composed of 5-layer pressure-responsive release microspheres and an essential oil composition filled inside the 5-layer pressure-responsive release microspheres and between the gaps of each layer. Among them, the material of the 5-layer pressure-responsive release microspheres includes 80wt% sodium alginate and 20wt% low molecular weight poly(N-isopropylacrylamide) with a molecular weight of 10,000; by weight percentage, the essential oil composition includes: 1% rosemary essential oil, 1% sandalwood essential oil, 1% ginger essential oil, 1% lavender essential oil, 2% cypress essential oil, 94% coconut oil.

[0051] The preparation method of this compound essential oil is as follows:

[0052] S1. Mix the aqueous solution of sodium alginate with a concentration of 2.5wt% and the aqueous solution of low molecular weight poly(N-isopropylacrylamide) with a concentration of 3wt% evenly according to the ratio to obtain a coating solution;

[0053] S2. Mix the essential oil composition and the coating solution at a mass ratio of 1:5, and homogenize at high speed (homogenize at a speed of 15,000 rpm at 25°C for 3 min) to form a primary emulsion. Then, drop the primary emulsion into a CaCl2 solution with a mass concentration of 2.5% at a speed of 0.6 mL / min, and stir magnetically at a speed of 250 rpm for 15 min to form solid microspheres with a diameter of 100 ± 5 μm. After centrifugal separation, wash with deionized water;

[0054] S3. Immerse the solid microspheres in a sufficient amount of essential oil composition and perform ultrasonic treatment (ultrasonic treatment at a power of 150 W at 25°C for 8 min) to enable the essential oil composition to adsorb on the surface and pores of the solid microspheres, and then centrifuge to remove the excess essential oil;

[0055] S4. Suspend the solid microspheres in a sufficient amount of coating solution and perform low-temperature atomization drying using a pressure atomizer (pressure is 0.9 MPa, temperature is 4°C). The atomized liquid droplets are directly sprayed into a -20°C cold trap, and a CaCl2 solution with a mass concentration of 1.5% is sprayed in the cold trap for primary cross-linking. Then, immerse the solid microspheres after spraying in a CaCl2 solution with a mass concentration of 1.5% for 6 min for secondary cross-linking;

[0056] S5. Take out the solid microspheres and place them in a freezing tray, freeze them to -90°C, and then transfer them to a freeze dryer and dry at -55°C for 48 h to obtain re-coated solid microspheres;

[0057] S6. Repeat steps S3 - S5 multiple times until the target coating layer number is reached.

[0058] Comparative Example 1

[0059] A compound essential oil for hair care massage, which is composed of 4 layers of pressure-responsive release microspheres and an essential oil composition filled inside the 4 layers of pressure-responsive release microspheres and between the gaps of each layer. Among them, the material of the 4 layers of pressure-responsive release microspheres is sodium alginate; by weight percentage, the essential oil composition includes: 2% rosemary essential oil, 1.5% sandalwood essential oil, 1% ginger essential oil, 2% lavender essential oil, 1.5% cypress essential oil, and 92% coconut oil.

[0060] The preparation method of this compound essential oil is as follows:

[0061] S1. Use an aqueous sodium alginate solution with a concentration of 2 wt% as the coating liquid;

[0062] S2. Mix the essential oil composition and the coating liquid at a mass ratio of 1:4, and perform high-speed homogenization (homogenize at a speed of 12000 rpm for 4 min at 22 °C) to form a primary emulsion. Then, drop the primary emulsion into a 2.5% CaCl2 solution at a speed of 0.5 mL / min, and magnetically stir at a speed of 200 rpm for 12 min to form solid microspheres with a diameter of 80 ± 5 μm. After centrifugal separation, wash with deionized water;

[0063] S3. Immerse the solid microspheres in a sufficient amount of essential oil composition, and perform ultrasonic treatment (ultrasonic treatment at a power of 120 W for 10 min at 22 °C) to make the essential oil composition adsorb on the surface and pores of the solid microspheres, and then centrifuge to remove the excess essential oil;

[0064] S4. Suspend the solid microspheres in a sufficient amount of coating liquid, and perform low-temperature atomization drying using a pressure atomizer (pressure is 0.8 MPa, temperature is 8 °C). The atomized liquid droplets are directly sprayed into a -20 °C cold trap, and a 1.5% CaCl2 solution is sprayed in the cold trap for primary cross-linking. Then, immerse the solid microspheres after spraying in a 1.5% CaCl2 solution for 5 min for secondary cross-linking;

[0065] S5. Take out the solid microspheres and place them in a freezing tray, freeze them to -80 °C, and then transfer them to a freeze dryer and dry at -50 °C for 36 h to obtain the re-coated solid microspheres;

[0066] S6. Repeat steps S3 - S5 multiple times until the target coating layer number is reached.

[0067] Comparative Example 2

[0068] A compound essential oil for hair care massage, the compound essential oil is composed of 4 layers of pressure-responsive release microspheres and an essential oil composition filled inside the 4 layers of pressure-responsive release microspheres and between the gaps of each layer. Among them, the material of the 4 layers of pressure-responsive release microspheres includes 50wt% sodium alginate and 50wt% low molecular weight poly(N-isopropylacrylamide) with a molecular weight of 5000; by weight percentage, the essential oil composition includes: 2% rosemary essential oil, 1.5% sandalwood essential oil, 1% ginger essential oil, 2% lavender essential oil, 1.5% cypress essential oil, 92% coconut oil.

[0069] The preparation method of the compound essential oil is as follows:

[0070] S1. Mix uniformly an aqueous solution of sodium alginate with a concentration of 2wt% and an aqueous solution of low molecular weight poly(N-isopropylacrylamide) with a concentration of 2wt% in proportion to obtain a coating solution;

[0071] S2. Mix the essential oil composition and the coating solution at a mass ratio of 1:4, and perform high-speed homogenization (homogenize at a speed of 12000 rpm for 4 min at 22°C) to form a primary emulsion. Then, drop the primary emulsion into a CaCl2 solution with a mass concentration of 2.5% at a speed of 0.5 mL / min, and perform magnetic stirring at a speed of 200 rpm for 12 min for cross-linking reaction to form solid microspheres with a diameter of 80 ± 5 μm. After centrifugal separation, wash with deionized water;

[0072] S3. Immerse the solid microspheres in a sufficient amount of essential oil composition and perform ultrasonic treatment (ultrasonic treatment at a power of 120 W for 10 min at 22°C) to enable the essential oil composition to adsorb on the surface and pores of the solid microspheres, and then centrifuge to remove the excess essential oil;

[0073] S4. Suspend the solid microspheres in a sufficient amount of coating solution and perform low-temperature atomization drying using a pressure atomizer (pressure is 0.8 MPa, temperature is 8°C). The atomized droplets are directly sprayed into a -20°C cold trap, and a CaCl2 solution with a mass concentration of 1.5% is sprayed in the cold trap for primary cross-linking. Then, immerse the solid microspheres after spraying in a CaCl2 solution with a mass concentration of 1.5% for 5 min for secondary cross-linking;

[0074] S5. Take out the solid microspheres and place them in a freezing tray, freeze to -80°C, and then transfer them to a freeze dryer and dry at -50°C for 36 h to obtain re-coated solid microspheres;

[0075] S6. Repeat steps S3 - S5 multiple times until the target coating layer number is reached.

[0076] Comparative Example 3

[0077] A compound essential oil for hair care massage, which is composed of four layers of pressure-responsive release microspheres and an essential oil composition filled inside the four layers of pressure-responsive release microspheres and between the gaps of each layer. Among them, the material of the four layers of pressure-responsive release microspheres includes 60 wt% of sodium alginate and 40 wt% of low molecular weight poly(N-isopropylacrylamide) with a molecular weight of 5000; by weight percentage, the essential oil composition includes: 2% rosemary essential oil, 1.5% sandalwood essential oil, 1% ginger essential oil, 2% lavender essential oil, 1.5% cypress essential oil, and 92% coconut oil.

[0078] The preparation method of this compound essential oil is as follows:

[0079] S1. Mix the aqueous solution of sodium alginate with a concentration of 2 wt% and the aqueous solution of low molecular weight poly(N-isopropylacrylamide) with a concentration of 2 wt% evenly according to the ratio to obtain a coating solution;

[0080] S2. Mix the essential oil composition and the coating solution at a mass ratio of 1:4, and homogenize at high speed (homogenize at a speed of 12000 rpm for 4 min at 22 °C) to form a primary emulsion. Then, drop the primary emulsion into a CaCl2 solution with a mass concentration of 2.5% at a speed of 0.5 mL / min, and stir magnetically at a speed of 200 rpm for 12 min for cross-linking reaction to form solid microspheres with a diameter of 80 ± 5 μm. After centrifugal separation, wash with deionized water;

[0081] S3. Immerse the solid microspheres in a sufficient amount of essential oil composition, and perform ultrasonic treatment (ultrasonic treatment with a power of 120 W for 10 min at 22 °C) to enable the essential oil composition to adsorb on the surface and pores of the solid microspheres, and then centrifuge to remove the excess essential oil;

[0082] S4. Suspend the solid microspheres in a sufficient amount of coating solution, and perform low-temperature atomization drying using a pressure atomizer (pressure is 0.8 MPa, temperature is 8 °C). The atomized liquid droplets are directly sprayed into a -20 °C cold trap, and a CaCl2 solution with a mass concentration of 1.5% is sprayed in the cold trap for primary cross-linking. Then, immerse the solid microspheres after spraying in a CaCl2 solution with a mass concentration of 1.5% for 5 min for secondary cross-linking;

[0083] S5. Take out the solid microspheres and place them in a freezing tray, freeze to -80 °C, and then transfer them to a freeze dryer and dry at -50 °C for 36 h to obtain re-coated solid microspheres;

[0084] S6. Repeat steps S3 - S5 multiple times until the target coating layer number is reached.

[0085] Comparative Example 4

[0086] A compound essential oil for hair care massage, the compound essential oil is composed of 4 layers of pressure-responsive release microspheres and an essential oil composition filled inside the 4 layers of pressure-responsive release microspheres and between the gaps of each layer. Among them, the material of the 4 layers of pressure-responsive release microspheres includes 70wt% sodium alginate and 30wt% low molecular weight poly(N-isopropylacrylamide) with a molecular weight of 5000; by weight percentage, the essential oil composition includes: 2% rosemary essential oil, 1.5% sandalwood essential oil, 1% ginger essential oil, 2% lavender essential oil, 1.5% cypress essential oil, 92% coconut oil.

[0087] The preparation method of the compound essential oil is as follows:

[0088] S1. Mix uniformly an aqueous solution of sodium alginate with a concentration of 2wt% and an aqueous solution of low molecular weight poly(N-isopropylacrylamide) with a concentration of 2wt% in proportion to obtain a coating solution;

[0089] S2. Mix the essential oil composition and the coating solution at a mass ratio of 1:4, and perform high-speed homogenization (homogenize at a speed of 12000rpm for 4min at 22°C) to form a primary emulsion. Then, drop the primary emulsion into a 2.5% CaCl2 solution at a speed of 0.5mL / min, and perform magnetic stirring at a speed of 200rpm for 12min of cross-linking reaction to form solid microspheres with a diameter of 80±5μm. After centrifugal separation, wash with deionized water;

[0090] S3. Immerse the solid microspheres in a sufficient amount of essential oil composition, and perform ultrasonic treatment (ultrasonic treatment at a power of 120W for 10min at 22°C) to enable the essential oil composition to adsorb on the surface and pores of the solid microspheres, and then centrifuge to remove the excess essential oil;

[0091] S4. Suspend the solid microspheres in a sufficient amount of coating solution, and perform low-temperature atomization drying using a pressure atomizer (pressure is 0.8MPa, temperature is 8°C). The atomized liquid droplets are directly sprayed into a -20°C cold trap, and a 1.5% CaCl2 solution is sprayed in the cold trap for primary cross-linking. Then, immerse the solid microspheres after spraying in a 1.5% CaCl2 solution for 5min for secondary cross-linking;

[0092] S5. Take out the solid microspheres and place them in a freezing tray, freeze them to -80°C, and then transfer them to a freeze dryer to dry at -50°C for 36h to obtain re-coated solid microspheres;

[0093] S6. Repeat steps S3 - S5 multiple times until the target coating layer number is reached.

[0094] Blank group

[0095] A compound essential oil for hair care massage, the compound essential oil includes by weight percentage: 2% rosemary essential oil, 1.5% sandalwood essential oil, 1% ginger essential oil, 2% lavender essential oil, 1.5% cypress essential oil, 92% coconut oil. This compound essential oil is directly obtained by mixing and stirring evenly.

[0096] III. Performance Test

[0097] (1) Safety Test:

[0098] Referring to the test methods in Chapter VII of the "Technical Specifications for Cosmetics Safety (2015 Edition)", the human skin patch test was adopted. 100 volunteers (with actual ages ranging from 20 to 55 years old) were selected as the test subjects (excluding insulin-dependent diabetes patients, patients with asthma or other chronic respiratory diseases under treatment, highly sensitive individuals, lactating or pregnant women, etc. Eligible volunteers were selected and signed an informed consent form), and the potential possibility of the compound essential oil in the above-mentioned Example 2, Comparative Examples 1-4, and the blank group causing adverse reactions on human skin was detected. The specific detection process is as follows: Put the compound essential oil into the small chamber of the patch tester, with a dosage of 0.02 ml. The control hole is distilled water for blank control. Apply the patch tester with the sample on the flexor side of the forearm of the subject, and gently press with the palm to make it evenly adhere to the skin for 24 h. Observe the skin reaction according to the grading standard in Table 2 below at 30 min, 24 h, and 48 h after removing the test patch tester, and record the results.

[0099] Table 2: Grading Standard for Skin Reactions in Occlusive Patch Tests

[0100]

[0101] Results: All 100 volunteers completed the 24-hour skin occlusive patch tests of Example 2, Comparative Examples 1-4, and the blank group. At 30 min, 24 h, and 48 h after removing the patch tester, the compound essential oil in each group did not cause adverse reactions to the skin, that is, all were grade 0 negative reactions. It shows that under normal circumstances, skin contact with the specified dose will not cause skin reactions, and all components can be used safely.

[0102] (2) Hair Care Massage Effect Test:

[0103] Select 120 volunteers who signed the informed consent form, aged 18 - 50 years old, with equal numbers of men and women, suffering from mild to moderate hair loss (Ludwig grade I-II) or damaged scalp barrier (TEWL≥15 g / m 2 / h) symptoms, all without a history of allergies, no history of hormone treatment, and excluding pregnancy / lactation, scalp infections, and recent use of hair growth drugs (such as minoxidil). The 120 volunteers were randomly divided into 6 groups, with each group containing 10 mild to moderate hair loss patients and 10 scalp barrier damaged patients.

[0104] Take the compound essential oil samples prepared in Example 2 above, Comparative Examples 1-4 and the blank group. Each time, take 2 mL of essential oil and evenly apply it to the scalp. Gently massage the scalp in a circular motion with the fingertips for 10 minutes (standard technique training), 3 times a week for 8 consecutive weeks. During the massage period, it is prohibited to use other hair care products (provide a unified silicone-free shampoo). The volunteers record daily whether there is any scalp discomfort / allergic reaction after use (appearance of erythema, infiltration, edema or papules, or obvious itching symptoms).

[0105] Then, using the German TrichoScan hair analysis system and referring to its user manual, calculate the hair count of the volunteers at the initial stage (day 0 of massage) and after the end (week 8) (unit: roots / cm 2 ). At the same time, using the Tewameter TM300 probe and referring to its user manual, measure the trans-epidermal water loss TEWL of the patients (unit: g / m2 / h).

[0106] The measurement results are statistically obtained in Table 3 below:

[0107] Table 3: Test results of the maintenance massage effect

[0108]

[0109] As can be seen from Table 3 above, the compound essential oil prepared in Example 2 of the present invention can achieve remarkable effects when applied to hair maintenance massage. On the one hand, the hair density increase rate reaches 22.06%, and the TEWL decrease rate reaches 27.87%. At the same time, during the entire maintenance process, there is no discomfort / allergic reaction. In Comparative Example 1, since the material of the pressure-responsive release microspheres only uses sodium alginate and does not add low molecular weight poly(N-isopropylacrylamide), it loses its thermosensitive properties, resulting in either difficulty in breaking the essential oil particles under massage pressure or multiple-layered and one-time breaking after increasing the massage pressure, leading to unstable sustained-release effects and thus poor overall maintenance effects. In addition, a small number of patients also experienced discomfort / allergic reactions. In Comparative Examples 2-4, the dosage ratio of sodium alginate and low molecular weight poly(N-isopropylacrylamide) in the pressure-responsive release microsphere material was adjusted. It can be seen that when the content of low molecular weight poly(N-isopropylacrylamide) exceeds 30%, the effect becomes worse as the content increases, and a very small number of patients also experienced discomfort / allergic reactions. This shows that the amount of low molecular weight poly(N-isopropylacrylamide) needs to be controlled within a certain range, otherwise it will affect the coating effect of the coating layer, and in some aspects, an excessive content even leads to a worse effect than without addition. The blank group directly uses the uncoated essential oil composition, which has the worst maintenance effect, and most patients experienced discomfort / allergic reactions.

[0110] The above-described embodiments merely represent several implementation manners of the present invention. The description thereof is relatively specific and detailed, but it should not be construed as a limitation to the scope of the patent for the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all fall within the protection scope of the present invention.

Claims

1. A compound essential oil for hair care and massage, characterized in that: The compound essential oil consists of multiple layers of pressure-responsive releasing microspheres and an essential oil composition filled inside the multiple layers of pressure-responsive releasing microspheres and between the gaps between the layers, wherein the material of the multiple layers of pressure-responsive releasing microspheres includes 80-99wt% of sodium alginate and 1-20wt% of low molecular weight poly (N-isopropylacrylamide).

2. The compound essential oil for hair care and massage according to claim 1, characterized in that: The molecular weight of the low molecular weight poly (N-isopropylacrylamide) is 2000-10000.

3. The compound essential oil for hair care and massage according to claim 1, characterized in that: The number of layers of the multi-layer pressure-responsive releasing microspheres is 3-5.

4. The compound essential oil for hair care and massage according to claim 1, characterized in that: The preparation method of the compound essential oil is: S1, mixing a sodium alginate aqueous solution with a concentration of 1.5-2.5wt% and a low molecular weight poly (N-isopropylacrylamide) aqueous solution with a concentration of 1-3wt% in proportion to obtain a coating solution; S2, the essential oil composition and the coating liquid are mixed at a mass ratio of 1:3-5, high-speed homogenization is performed to form a primary emulsion, and then the primary emulsion is dropped into a CaCl2 solution with a mass concentration of 2-2.5%, and magnetic stirring is performed at a speed of 180-250rpm, and a cross-linking reaction is performed for 10-15min to form solid microspheres with a diameter of 50-100μm, and the solid microspheres are washed with deionized water after centrifugation; S3, immersing the solid microspheres in the essential oil composition, ultrasonically treating the solid microspheres so that the essential oil composition is adsorbed on the surface and pores of the solid microspheres, and then centrifuging to remove excess essential oil; S4, suspending the solid microspheres in the coating liquid, and using a pressurized atomizer for low-temperature atomization drying, spraying the atomized droplets directly into a -18°C to -20°C cold trap, spraying a CaCl2 solution with a mass concentration of 1-1.5% in the cold trap for primary crosslinking, and then immersing the sprayed solid microspheres in a CaCl2 solution with a mass concentration of 1-1.5% for 4-6 minutes for secondary crosslinking; S5, taking out the solid microspheres and placing them in a freezing tray, freezing them to -70°C to -90°C, and then transferring them to a freeze dryer, drying them at -45°C to -55°C for 24-48 hours to obtain re-coated solid microspheres; S6. Repeat steps S3-S5 multiple times until the target number of coating layers is reached.

5. The compound essential oil for hair care and massage according to claim 4, characterized in that: In step S2, the high-speed homogenization conditions are: homogenization at a speed of 10000-15000 rpm for 3-6 minutes at 20-25°C.

6. The compound essential oil for hair care and massage according to claim 4, characterized in that: In step S2, the flow rate of the primary emulsion dripping is 0.4-0.6 mL / min.

7. The compound essential oil for hair care and massage according to claim 4, characterized in that: In step S3, the ultrasonic treatment is carried out under the conditions of: ultrasonic treatment at a power of 100-150 W for 8-12 min at 20-25°C.

8. The compound essential oil for hair care and massage according to claim 4, characterized in that: In step S4, the conditions for low-temperature atomization drying are: pressure of 0.7-0.9 MPa and temperature of 4-10°C.

9. The compound essential oil for hair care and massage according to claim 1, characterized in that: By weight percentage, the essential oil composition comprises: 1-3% rosemary essential oil, 1-2% sandalwood essential oil, 0.5-1% ginger essential oil, 1-3% lavender essential oil, 1-2% cypress essential oil, and the remainder is coconut oil as a base oil.

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